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  <div class="section" id="module-urllib">
<span id="urllib-open-arbitrary-resources-by-url"></span><h1>20.5. <a class="reference internal" href="#module-urllib" title="urllib: Open an arbitrary network resource by URL (requires sockets)."><tt class="xref py py-mod docutils literal"><span class="pre">urllib</span></tt></a> &#8212; Open arbitrary resources by URL<a class="headerlink" href="#module-urllib" title="Permalink to this headline">¶</a></h1>
<div class="admonition note">
<p class="first admonition-title">Note</p>
<p class="last">The <a class="reference internal" href="#module-urllib" title="urllib: Open an arbitrary network resource by URL (requires sockets)."><tt class="xref py py-mod docutils literal"><span class="pre">urllib</span></tt></a> module has been split into parts and renamed in
Python 3 to <tt class="xref py py-mod docutils literal"><span class="pre">urllib.request</span></tt>, <tt class="xref py py-mod docutils literal"><span class="pre">urllib.parse</span></tt>,
and <tt class="xref py py-mod docutils literal"><span class="pre">urllib.error</span></tt>. The <a class="reference internal" href="../glossary.html#term-to3"><em class="xref std std-term">2to3</em></a> tool will automatically adapt
imports when converting your sources to Python 3.
Also note that the <tt class="xref py py-func docutils literal"><span class="pre">urllib.request.urlopen()</span></tt> function in Python 3 is
equivalent to <a class="reference internal" href="urllib2.html#urllib2.urlopen" title="urllib2.urlopen"><tt class="xref py py-func docutils literal"><span class="pre">urllib2.urlopen()</span></tt></a> and that <a class="reference internal" href="#urllib.urlopen" title="urllib.urlopen"><tt class="xref py py-func docutils literal"><span class="pre">urllib.urlopen()</span></tt></a> has
been removed.</p>
</div>
<p id="index-0">This module provides a high-level interface for fetching data across the World
Wide Web.  In particular, the <a class="reference internal" href="#urllib.urlopen" title="urllib.urlopen"><tt class="xref py py-func docutils literal"><span class="pre">urlopen()</span></tt></a> function is similar to the
built-in function <a class="reference internal" href="functions.html#open" title="open"><tt class="xref py py-func docutils literal"><span class="pre">open()</span></tt></a>, but accepts Universal Resource Locators (URLs)
instead of filenames.  Some restrictions apply &#8212; it can only open URLs for
reading, and no seek operations are available.</p>
<div class="admonition warning">
<p class="first admonition-title">Warning</p>
<p class="last">When opening HTTPS URLs, it does not attempt to validate the
server certificate.  Use at your own risk!</p>
</div>
<div class="section" id="high-level-interface">
<h2>20.5.1. High-level interface<a class="headerlink" href="#high-level-interface" title="Permalink to this headline">¶</a></h2>
<dl class="function">
<dt id="urllib.urlopen">
<tt class="descclassname">urllib.</tt><tt class="descname">urlopen</tt><big>(</big><em>url</em><span class="optional">[</span>, <em>data</em><span class="optional">[</span>, <em>proxies</em><span class="optional">]</span><span class="optional">]</span><big>)</big><a class="headerlink" href="#urllib.urlopen" title="Permalink to this definition">¶</a></dt>
<dd><p>Open a network object denoted by a URL for reading.  If the URL does not
have a scheme identifier, or if it has <tt class="file docutils literal"><span class="pre">file:</span></tt> as its scheme
identifier, this opens a local file (without <a class="reference internal" href="../glossary.html#term-universal-newlines"><em class="xref std std-term">universal newlines</em></a>);
otherwise it opens a socket to a server somewhere on the network.  If the
connection cannot be made the <a class="reference internal" href="exceptions.html#exceptions.IOError" title="exceptions.IOError"><tt class="xref py py-exc docutils literal"><span class="pre">IOError</span></tt></a> exception is raised.  If all
went well, a file-like object is returned.  This supports the following
methods: <tt class="xref py py-meth docutils literal"><span class="pre">read()</span></tt>, <a class="reference internal" href="readline.html#module-readline" title="readline: GNU readline support for Python. (Unix)"><tt class="xref py py-meth docutils literal"><span class="pre">readline()</span></tt></a>, <tt class="xref py py-meth docutils literal"><span class="pre">readlines()</span></tt>, <tt class="xref py py-meth docutils literal"><span class="pre">fileno()</span></tt>,
<tt class="xref py py-meth docutils literal"><span class="pre">close()</span></tt>, <tt class="xref py py-meth docutils literal"><span class="pre">info()</span></tt>, <tt class="xref py py-meth docutils literal"><span class="pre">getcode()</span></tt> and <tt class="xref py py-meth docutils literal"><span class="pre">geturl()</span></tt>.  It also
has proper support for the <a class="reference internal" href="../glossary.html#term-iterator"><em class="xref std std-term">iterator</em></a> protocol. One caveat: the
<tt class="xref py py-meth docutils literal"><span class="pre">read()</span></tt> method, if the size argument is omitted or negative, may not
read until the end of the data stream; there is no good way to determine
that the entire stream from a socket has been read in the general case.</p>
<p>Except for the <tt class="xref py py-meth docutils literal"><span class="pre">info()</span></tt>, <tt class="xref py py-meth docutils literal"><span class="pre">getcode()</span></tt> and <tt class="xref py py-meth docutils literal"><span class="pre">geturl()</span></tt> methods,
these methods have the same interface as for file objects &#8212; see section
<a class="reference internal" href="stdtypes.html#bltin-file-objects"><em>File Objects</em></a> in this manual.  (It is not a built-in file object,
however, so it can&#8217;t be used at those few places where a true built-in file
object is required.)</p>
<p id="index-1">The <tt class="xref py py-meth docutils literal"><span class="pre">info()</span></tt> method returns an instance of the class
<a class="reference internal" href="mimetools.html#mimetools.Message" title="mimetools.Message"><tt class="xref py py-class docutils literal"><span class="pre">mimetools.Message</span></tt></a> containing meta-information associated with the
URL.  When the method is HTTP, these headers are those returned by the server
at the head of the retrieved HTML page (including Content-Length and
Content-Type).  When the method is FTP, a Content-Length header will be
present if (as is now usual) the server passed back a file length in response
to the FTP retrieval request. A Content-Type header will be present if the
MIME type can be guessed.  When the method is local-file, returned headers
will include a Date representing the file&#8217;s last-modified time, a
Content-Length giving file size, and a Content-Type containing a guess at the
file&#8217;s type. See also the description of the <a class="reference internal" href="mimetools.html#module-mimetools" title="mimetools: Tools for parsing MIME-style message bodies. (deprecated)"><tt class="xref py py-mod docutils literal"><span class="pre">mimetools</span></tt></a> module.</p>
<p>The <tt class="xref py py-meth docutils literal"><span class="pre">geturl()</span></tt> method returns the real URL of the page.  In some cases, the
HTTP server redirects a client to another URL.  The <a class="reference internal" href="#urllib.urlopen" title="urllib.urlopen"><tt class="xref py py-func docutils literal"><span class="pre">urlopen()</span></tt></a> function
handles this transparently, but in some cases the caller needs to know which URL
the client was redirected to.  The <tt class="xref py py-meth docutils literal"><span class="pre">geturl()</span></tt> method can be used to get at
this redirected URL.</p>
<p>The <tt class="xref py py-meth docutils literal"><span class="pre">getcode()</span></tt> method returns the HTTP status code that was sent with the
response, or <tt class="xref docutils literal"><span class="pre">None</span></tt> if the URL is no HTTP URL.</p>
<p>If the <em>url</em> uses the <tt class="file docutils literal"><span class="pre">http:</span></tt> scheme identifier, the optional <em>data</em>
argument may be given to specify a <tt class="docutils literal"><span class="pre">POST</span></tt> request (normally the request type
is <tt class="docutils literal"><span class="pre">GET</span></tt>).  The <em>data</em> argument must be in standard
<em class="mimetype">application/x-www-form-urlencoded</em> format; see the <a class="reference internal" href="#urllib.urlencode" title="urllib.urlencode"><tt class="xref py py-func docutils literal"><span class="pre">urlencode()</span></tt></a>
function below.</p>
<p>The <a class="reference internal" href="#urllib.urlopen" title="urllib.urlopen"><tt class="xref py py-func docutils literal"><span class="pre">urlopen()</span></tt></a> function works transparently with proxies which do not
require authentication.  In a Unix or Windows environment, set the
<span class="target" id="index-2"></span><tt class="xref std std-envvar docutils literal"><span class="pre">http_proxy</span></tt>, or <span class="target" id="index-3"></span><tt class="xref std std-envvar docutils literal"><span class="pre">ftp_proxy</span></tt> environment variables to a URL that
identifies the proxy server before starting the Python interpreter.  For example
(the <tt class="docutils literal"><span class="pre">'%'</span></tt> is the command prompt):</p>
<div class="highlight-python"><pre>% http_proxy="http://www.someproxy.com:3128"
% export http_proxy
% python
...</pre>
</div>
<p>The <span class="target" id="index-4"></span><tt class="xref std std-envvar docutils literal"><span class="pre">no_proxy</span></tt> environment variable can be used to specify hosts which
shouldn&#8217;t be reached via proxy; if set, it should be a comma-separated list
of hostname suffixes, optionally with <tt class="docutils literal"><span class="pre">:port</span></tt> appended, for example
<tt class="docutils literal"><span class="pre">cern.ch,ncsa.uiuc.edu,some.host:8080</span></tt>.</p>
<p>In a Windows environment, if no proxy environment variables are set, proxy
settings are obtained from the registry&#8217;s Internet Settings section.</p>
<p id="index-5">In a Mac OS X  environment, <a class="reference internal" href="#urllib.urlopen" title="urllib.urlopen"><tt class="xref py py-func docutils literal"><span class="pre">urlopen()</span></tt></a> will retrieve proxy information
from the OS X System Configuration Framework, which can be managed with
Network System Preferences panel.</p>
<p>Alternatively, the optional <em>proxies</em> argument may be used to explicitly specify
proxies.  It must be a dictionary mapping scheme names to proxy URLs, where an
empty dictionary causes no proxies to be used, and <tt class="xref docutils literal"><span class="pre">None</span></tt> (the default value)
causes environmental proxy settings to be used as discussed above.  For
example:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="c"># Use http://www.someproxy.com:3128 for http proxying</span>
<span class="n">proxies</span> <span class="o">=</span> <span class="p">{</span><span class="s">&#39;http&#39;</span><span class="p">:</span> <span class="s">&#39;http://www.someproxy.com:3128&#39;</span><span class="p">}</span>
<span class="n">filehandle</span> <span class="o">=</span> <span class="n">urllib</span><span class="o">.</span><span class="n">urlopen</span><span class="p">(</span><span class="n">some_url</span><span class="p">,</span> <span class="n">proxies</span><span class="o">=</span><span class="n">proxies</span><span class="p">)</span>
<span class="c"># Don&#39;t use any proxies</span>
<span class="n">filehandle</span> <span class="o">=</span> <span class="n">urllib</span><span class="o">.</span><span class="n">urlopen</span><span class="p">(</span><span class="n">some_url</span><span class="p">,</span> <span class="n">proxies</span><span class="o">=</span><span class="p">{})</span>
<span class="c"># Use proxies from environment - both versions are equivalent</span>
<span class="n">filehandle</span> <span class="o">=</span> <span class="n">urllib</span><span class="o">.</span><span class="n">urlopen</span><span class="p">(</span><span class="n">some_url</span><span class="p">,</span> <span class="n">proxies</span><span class="o">=</span><span class="bp">None</span><span class="p">)</span>
<span class="n">filehandle</span> <span class="o">=</span> <span class="n">urllib</span><span class="o">.</span><span class="n">urlopen</span><span class="p">(</span><span class="n">some_url</span><span class="p">)</span>
</pre></div>
</div>
<p>Proxies which require authentication for use are not currently supported; this
is considered an implementation limitation.</p>
<p class="versionchanged">
<span class="versionmodified">Changed in version 2.3: </span>Added the <em>proxies</em> support.</p>
<p class="versionchanged">
<span class="versionmodified">Changed in version 2.6: </span>Added <tt class="xref py py-meth docutils literal"><span class="pre">getcode()</span></tt> to returned object and support for the
<span class="target" id="index-6"></span><tt class="xref std std-envvar docutils literal"><span class="pre">no_proxy</span></tt> environment variable.</p>
<p class="deprecated">
<span class="versionmodified">Deprecated since version 2.6: </span>The <a class="reference internal" href="#urllib.urlopen" title="urllib.urlopen"><tt class="xref py py-func docutils literal"><span class="pre">urlopen()</span></tt></a> function has been removed in Python 3 in favor
of <a class="reference internal" href="urllib2.html#urllib2.urlopen" title="urllib2.urlopen"><tt class="xref py py-func docutils literal"><span class="pre">urllib2.urlopen()</span></tt></a>.</p>
</dd></dl>

<dl class="function">
<dt id="urllib.urlretrieve">
<tt class="descclassname">urllib.</tt><tt class="descname">urlretrieve</tt><big>(</big><em>url</em><span class="optional">[</span>, <em>filename</em><span class="optional">[</span>, <em>reporthook</em><span class="optional">[</span>, <em>data</em><span class="optional">]</span><span class="optional">]</span><span class="optional">]</span><big>)</big><a class="headerlink" href="#urllib.urlretrieve" title="Permalink to this definition">¶</a></dt>
<dd><p>Copy a network object denoted by a URL to a local file, if necessary. If the URL
points to a local file, or a valid cached copy of the object exists, the object
is not copied.  Return a tuple <tt class="docutils literal"><span class="pre">(filename,</span> <span class="pre">headers)</span></tt> where <em>filename</em> is the
local file name under which the object can be found, and <em>headers</em> is whatever
the <tt class="xref py py-meth docutils literal"><span class="pre">info()</span></tt> method of the object returned by <a class="reference internal" href="#urllib.urlopen" title="urllib.urlopen"><tt class="xref py py-func docutils literal"><span class="pre">urlopen()</span></tt></a> returned (for
a remote object, possibly cached). Exceptions are the same as for
<a class="reference internal" href="#urllib.urlopen" title="urllib.urlopen"><tt class="xref py py-func docutils literal"><span class="pre">urlopen()</span></tt></a>.</p>
<p>The second argument, if present, specifies the file location to copy to (if
absent, the location will be a tempfile with a generated name). The third
argument, if present, is a hook function that will be called once on
establishment of the network connection and once after each block read
thereafter.  The hook will be passed three arguments; a count of blocks
transferred so far, a block size in bytes, and the total size of the file.  The
third argument may be <tt class="docutils literal"><span class="pre">-1</span></tt> on older FTP servers which do not return a file
size in response to a retrieval request.</p>
<p>If the <em>url</em> uses the <tt class="file docutils literal"><span class="pre">http:</span></tt> scheme identifier, the optional <em>data</em>
argument may be given to specify a <tt class="docutils literal"><span class="pre">POST</span></tt> request (normally the request type
is <tt class="docutils literal"><span class="pre">GET</span></tt>).  The <em>data</em> argument must in standard
<em class="mimetype">application/x-www-form-urlencoded</em> format; see the <a class="reference internal" href="#urllib.urlencode" title="urllib.urlencode"><tt class="xref py py-func docutils literal"><span class="pre">urlencode()</span></tt></a>
function below.</p>
<p class="versionchanged">
<span class="versionmodified">Changed in version 2.5: </span><a class="reference internal" href="#urllib.urlretrieve" title="urllib.urlretrieve"><tt class="xref py py-func docutils literal"><span class="pre">urlretrieve()</span></tt></a> will raise <a class="reference internal" href="#urllib.ContentTooShortError" title="urllib.ContentTooShortError"><tt class="xref py py-exc docutils literal"><span class="pre">ContentTooShortError</span></tt></a> when it detects that
the amount of data available  was less than the expected amount (which is the
size reported by a  <em>Content-Length</em> header). This can occur, for example, when
the  download is interrupted.<p>The <em>Content-Length</em> is treated as a lower bound: if there&#8217;s more data  to read,
<a class="reference internal" href="#urllib.urlretrieve" title="urllib.urlretrieve"><tt class="xref py py-func docutils literal"><span class="pre">urlretrieve()</span></tt></a> reads more data, but if less data is available,  it raises
the exception.</p>
<p>You can still retrieve the downloaded data in this case, it is stored  in the
<tt class="xref py py-attr docutils literal"><span class="pre">content</span></tt> attribute of the exception instance.</p>
<p>If no <em>Content-Length</em> header was supplied, <a class="reference internal" href="#urllib.urlretrieve" title="urllib.urlretrieve"><tt class="xref py py-func docutils literal"><span class="pre">urlretrieve()</span></tt></a> can not check
the size of the data it has downloaded, and just returns it.  In this case you
just have to assume that the download was successful.</p>
</p>
</dd></dl>

<dl class="data">
<dt id="urllib._urlopener">
<tt class="descclassname">urllib.</tt><tt class="descname">_urlopener</tt><a class="headerlink" href="#urllib._urlopener" title="Permalink to this definition">¶</a></dt>
<dd><p>The public functions <a class="reference internal" href="#urllib.urlopen" title="urllib.urlopen"><tt class="xref py py-func docutils literal"><span class="pre">urlopen()</span></tt></a> and <a class="reference internal" href="#urllib.urlretrieve" title="urllib.urlretrieve"><tt class="xref py py-func docutils literal"><span class="pre">urlretrieve()</span></tt></a> create an instance
of the <a class="reference internal" href="#urllib.FancyURLopener" title="urllib.FancyURLopener"><tt class="xref py py-class docutils literal"><span class="pre">FancyURLopener</span></tt></a> class and use it to perform their requested
actions.  To override this functionality, programmers can create a subclass of
<a class="reference internal" href="#urllib.URLopener" title="urllib.URLopener"><tt class="xref py py-class docutils literal"><span class="pre">URLopener</span></tt></a> or <a class="reference internal" href="#urllib.FancyURLopener" title="urllib.FancyURLopener"><tt class="xref py py-class docutils literal"><span class="pre">FancyURLopener</span></tt></a>, then assign an instance of that
class to the <tt class="docutils literal"><span class="pre">urllib._urlopener</span></tt> variable before calling the desired function.
For example, applications may want to specify a different
<em class="mailheader">User-Agent</em> header than <a class="reference internal" href="#urllib.URLopener" title="urllib.URLopener"><tt class="xref py py-class docutils literal"><span class="pre">URLopener</span></tt></a> defines.  This can be
accomplished with the following code:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">import</span> <span class="nn">urllib</span>

<span class="k">class</span> <span class="nc">AppURLopener</span><span class="p">(</span><span class="n">urllib</span><span class="o">.</span><span class="n">FancyURLopener</span><span class="p">):</span>
    <span class="n">version</span> <span class="o">=</span> <span class="s">&quot;App/1.7&quot;</span>

<span class="n">urllib</span><span class="o">.</span><span class="n">_urlopener</span> <span class="o">=</span> <span class="n">AppURLopener</span><span class="p">()</span>
</pre></div>
</div>
</dd></dl>

<dl class="function">
<dt id="urllib.urlcleanup">
<tt class="descclassname">urllib.</tt><tt class="descname">urlcleanup</tt><big>(</big><big>)</big><a class="headerlink" href="#urllib.urlcleanup" title="Permalink to this definition">¶</a></dt>
<dd><p>Clear the cache that may have been built up by previous calls to
<a class="reference internal" href="#urllib.urlretrieve" title="urllib.urlretrieve"><tt class="xref py py-func docutils literal"><span class="pre">urlretrieve()</span></tt></a>.</p>
</dd></dl>

</div>
<div class="section" id="utility-functions">
<h2>20.5.2. Utility functions<a class="headerlink" href="#utility-functions" title="Permalink to this headline">¶</a></h2>
<dl class="function">
<dt id="urllib.quote">
<tt class="descclassname">urllib.</tt><tt class="descname">quote</tt><big>(</big><em>string</em><span class="optional">[</span>, <em>safe</em><span class="optional">]</span><big>)</big><a class="headerlink" href="#urllib.quote" title="Permalink to this definition">¶</a></dt>
<dd><p>Replace special characters in <em>string</em> using the <tt class="docutils literal"><span class="pre">%xx</span></tt> escape. Letters,
digits, and the characters <tt class="docutils literal"><span class="pre">'_.-'</span></tt> are never quoted. By default, this
function is intended for quoting the path section of the URL. The optional
<em>safe</em> parameter specifies additional characters that should not be quoted
&#8212; its default value is <tt class="docutils literal"><span class="pre">'/'</span></tt>.</p>
<p>Example: <tt class="docutils literal"><span class="pre">quote('/~connolly/')</span></tt> yields <tt class="docutils literal"><span class="pre">'/%7econnolly/'</span></tt>.</p>
</dd></dl>

<dl class="function">
<dt id="urllib.quote_plus">
<tt class="descclassname">urllib.</tt><tt class="descname">quote_plus</tt><big>(</big><em>string</em><span class="optional">[</span>, <em>safe</em><span class="optional">]</span><big>)</big><a class="headerlink" href="#urllib.quote_plus" title="Permalink to this definition">¶</a></dt>
<dd><p>Like <a class="reference internal" href="#urllib.quote" title="urllib.quote"><tt class="xref py py-func docutils literal"><span class="pre">quote()</span></tt></a>, but also replaces spaces by plus signs, as required for
quoting HTML form values when building up a query string to go into a URL.
Plus signs in the original string are escaped unless they are included in
<em>safe</em>.  It also does not have <em>safe</em> default to <tt class="docutils literal"><span class="pre">'/'</span></tt>.</p>
</dd></dl>

<dl class="function">
<dt id="urllib.unquote">
<tt class="descclassname">urllib.</tt><tt class="descname">unquote</tt><big>(</big><em>string</em><big>)</big><a class="headerlink" href="#urllib.unquote" title="Permalink to this definition">¶</a></dt>
<dd><p>Replace <tt class="docutils literal"><span class="pre">%xx</span></tt> escapes by their single-character equivalent.</p>
<p>Example: <tt class="docutils literal"><span class="pre">unquote('/%7Econnolly/')</span></tt> yields <tt class="docutils literal"><span class="pre">'/~connolly/'</span></tt>.</p>
</dd></dl>

<dl class="function">
<dt id="urllib.unquote_plus">
<tt class="descclassname">urllib.</tt><tt class="descname">unquote_plus</tt><big>(</big><em>string</em><big>)</big><a class="headerlink" href="#urllib.unquote_plus" title="Permalink to this definition">¶</a></dt>
<dd><p>Like <a class="reference internal" href="#urllib.unquote" title="urllib.unquote"><tt class="xref py py-func docutils literal"><span class="pre">unquote()</span></tt></a>, but also replaces plus signs by spaces, as required for
unquoting HTML form values.</p>
</dd></dl>

<dl class="function">
<dt id="urllib.urlencode">
<tt class="descclassname">urllib.</tt><tt class="descname">urlencode</tt><big>(</big><em>query</em><span class="optional">[</span>, <em>doseq</em><span class="optional">]</span><big>)</big><a class="headerlink" href="#urllib.urlencode" title="Permalink to this definition">¶</a></dt>
<dd><p>Convert a mapping object or a sequence of two-element tuples to a
&#8220;percent-encoded&#8221; string, suitable to pass to <a class="reference internal" href="#urllib.urlopen" title="urllib.urlopen"><tt class="xref py py-func docutils literal"><span class="pre">urlopen()</span></tt></a> above as the
optional <em>data</em> argument.  This is useful to pass a dictionary of form
fields to a <tt class="docutils literal"><span class="pre">POST</span></tt> request.  The resulting string is a series of
<tt class="docutils literal"><span class="pre">key=value</span></tt> pairs separated by <tt class="docutils literal"><span class="pre">'&amp;'</span></tt> characters, where both <em>key</em> and
<em>value</em> are quoted using <a class="reference internal" href="#urllib.quote_plus" title="urllib.quote_plus"><tt class="xref py py-func docutils literal"><span class="pre">quote_plus()</span></tt></a> above.  When a sequence of
two-element tuples is used as the <em>query</em> argument, the first element of
each tuple is a key and the second is a value. The value element in itself
can be a sequence and in that case, if the optional parameter <em>doseq</em> is
evaluates to <em>True</em>, individual <tt class="docutils literal"><span class="pre">key=value</span></tt> pairs separated by <tt class="docutils literal"><span class="pre">'&amp;'</span></tt> are
generated for each element of the value sequence for the key.  The order of
parameters in the encoded string will match the order of parameter tuples in
the sequence. The <a class="reference internal" href="urlparse.html#module-urlparse" title="urlparse: Parse URLs into or assemble them from components."><tt class="xref py py-mod docutils literal"><span class="pre">urlparse</span></tt></a> module provides the functions
<tt class="xref py py-func docutils literal"><span class="pre">parse_qs()</span></tt> and <tt class="xref py py-func docutils literal"><span class="pre">parse_qsl()</span></tt> which are used to parse query strings
into Python data structures.</p>
</dd></dl>

<dl class="function">
<dt id="urllib.pathname2url">
<tt class="descclassname">urllib.</tt><tt class="descname">pathname2url</tt><big>(</big><em>path</em><big>)</big><a class="headerlink" href="#urllib.pathname2url" title="Permalink to this definition">¶</a></dt>
<dd><p>Convert the pathname <em>path</em> from the local syntax for a path to the form used in
the path component of a URL.  This does not produce a complete URL.  The return
value will already be quoted using the <a class="reference internal" href="#urllib.quote" title="urllib.quote"><tt class="xref py py-func docutils literal"><span class="pre">quote()</span></tt></a> function.</p>
</dd></dl>

<dl class="function">
<dt id="urllib.url2pathname">
<tt class="descclassname">urllib.</tt><tt class="descname">url2pathname</tt><big>(</big><em>path</em><big>)</big><a class="headerlink" href="#urllib.url2pathname" title="Permalink to this definition">¶</a></dt>
<dd><p>Convert the path component <em>path</em> from an percent-encoded URL to the local syntax for a
path.  This does not accept a complete URL.  This function uses <a class="reference internal" href="#urllib.unquote" title="urllib.unquote"><tt class="xref py py-func docutils literal"><span class="pre">unquote()</span></tt></a>
to decode <em>path</em>.</p>
</dd></dl>

<dl class="function">
<dt id="urllib.getproxies">
<tt class="descclassname">urllib.</tt><tt class="descname">getproxies</tt><big>(</big><big>)</big><a class="headerlink" href="#urllib.getproxies" title="Permalink to this definition">¶</a></dt>
<dd><p>This helper function returns a dictionary of scheme to proxy server URL
mappings. It scans the environment for variables named <tt class="docutils literal"><span class="pre">&lt;scheme&gt;_proxy</span></tt>,
in case insensitive way, for all operating systems first, and when it cannot
find it, looks for proxy information from Mac OSX System Configuration for
Mac OS X and Windows Systems Registry for Windows.</p>
</dd></dl>

<div class="admonition note">
<p class="first admonition-title">Note</p>
<p class="last">urllib also exposes certain utility functions like splittype, splithost and
others parsing url into various components. But it is recommended to use
<a class="reference internal" href="urlparse.html#module-urlparse" title="urlparse: Parse URLs into or assemble them from components."><tt class="xref py py-mod docutils literal"><span class="pre">urlparse</span></tt></a> for parsing urls than using these functions directly.
Python 3 does not expose these helper functions from <tt class="xref py py-mod docutils literal"><span class="pre">urllib.parse</span></tt>
module.</p>
</div>
</div>
<div class="section" id="url-opener-objects">
<h2>20.5.3. URL Opener objects<a class="headerlink" href="#url-opener-objects" title="Permalink to this headline">¶</a></h2>
<dl class="class">
<dt id="urllib.URLopener">
<em class="property">class </em><tt class="descclassname">urllib.</tt><tt class="descname">URLopener</tt><big>(</big><span class="optional">[</span><em>proxies</em><span class="optional">[</span>, <em>**x509</em><span class="optional">]</span><span class="optional">]</span><big>)</big><a class="headerlink" href="#urllib.URLopener" title="Permalink to this definition">¶</a></dt>
<dd><p>Base class for opening and reading URLs.  Unless you need to support opening
objects using schemes other than <tt class="file docutils literal"><span class="pre">http:</span></tt>, <tt class="file docutils literal"><span class="pre">ftp:</span></tt>, or <tt class="file docutils literal"><span class="pre">file:</span></tt>,
you probably want to use <a class="reference internal" href="#urllib.FancyURLopener" title="urllib.FancyURLopener"><tt class="xref py py-class docutils literal"><span class="pre">FancyURLopener</span></tt></a>.</p>
<p>By default, the <a class="reference internal" href="#urllib.URLopener" title="urllib.URLopener"><tt class="xref py py-class docutils literal"><span class="pre">URLopener</span></tt></a> class sends a <em class="mailheader">User-Agent</em> header
of <tt class="docutils literal"><span class="pre">urllib/VVV</span></tt>, where <em>VVV</em> is the <a class="reference internal" href="#module-urllib" title="urllib: Open an arbitrary network resource by URL (requires sockets)."><tt class="xref py py-mod docutils literal"><span class="pre">urllib</span></tt></a> version number.
Applications can define their own <em class="mailheader">User-Agent</em> header by subclassing
<a class="reference internal" href="#urllib.URLopener" title="urllib.URLopener"><tt class="xref py py-class docutils literal"><span class="pre">URLopener</span></tt></a> or <a class="reference internal" href="#urllib.FancyURLopener" title="urllib.FancyURLopener"><tt class="xref py py-class docutils literal"><span class="pre">FancyURLopener</span></tt></a> and setting the class attribute
<a class="reference internal" href="#urllib.URLopener.version" title="urllib.URLopener.version"><tt class="xref py py-attr docutils literal"><span class="pre">version</span></tt></a> to an appropriate string value in the subclass definition.</p>
<p>The optional <em>proxies</em> parameter should be a dictionary mapping scheme names to
proxy URLs, where an empty dictionary turns proxies off completely.  Its default
value is <tt class="xref docutils literal"><span class="pre">None</span></tt>, in which case environmental proxy settings will be used if
present, as discussed in the definition of <a class="reference internal" href="#urllib.urlopen" title="urllib.urlopen"><tt class="xref py py-func docutils literal"><span class="pre">urlopen()</span></tt></a>, above.</p>
<p>Additional keyword parameters, collected in <em>x509</em>, may be used for
authentication of the client when using the <tt class="file docutils literal"><span class="pre">https:</span></tt> scheme.  The keywords
<em>key_file</em> and <em>cert_file</em> are supported to provide an  SSL key and certificate;
both are needed to support client authentication.</p>
<p><a class="reference internal" href="#urllib.URLopener" title="urllib.URLopener"><tt class="xref py py-class docutils literal"><span class="pre">URLopener</span></tt></a> objects will raise an <a class="reference internal" href="exceptions.html#exceptions.IOError" title="exceptions.IOError"><tt class="xref py py-exc docutils literal"><span class="pre">IOError</span></tt></a> exception if the server
returns an error code.</p>
<blockquote>
<div><dl class="method">
<dt id="urllib.URLopener.open">
<tt class="descname">open</tt><big>(</big><em>fullurl</em><span class="optional">[</span>, <em>data</em><span class="optional">]</span><big>)</big><a class="headerlink" href="#urllib.URLopener.open" title="Permalink to this definition">¶</a></dt>
<dd><p>Open <em>fullurl</em> using the appropriate protocol.  This method sets up cache and
proxy information, then calls the appropriate open method with its input
arguments.  If the scheme is not recognized, <a class="reference internal" href="#urllib.URLopener.open_unknown" title="urllib.URLopener.open_unknown"><tt class="xref py py-meth docutils literal"><span class="pre">open_unknown()</span></tt></a> is called.
The <em>data</em> argument has the same meaning as the <em>data</em> argument of
<a class="reference internal" href="#urllib.urlopen" title="urllib.urlopen"><tt class="xref py py-func docutils literal"><span class="pre">urlopen()</span></tt></a>.</p>
</dd></dl>

<dl class="method">
<dt id="urllib.URLopener.open_unknown">
<tt class="descname">open_unknown</tt><big>(</big><em>fullurl</em><span class="optional">[</span>, <em>data</em><span class="optional">]</span><big>)</big><a class="headerlink" href="#urllib.URLopener.open_unknown" title="Permalink to this definition">¶</a></dt>
<dd><p>Overridable interface to open unknown URL types.</p>
</dd></dl>

<dl class="method">
<dt id="urllib.URLopener.retrieve">
<tt class="descname">retrieve</tt><big>(</big><em>url</em><span class="optional">[</span>, <em>filename</em><span class="optional">[</span>, <em>reporthook</em><span class="optional">[</span>, <em>data</em><span class="optional">]</span><span class="optional">]</span><span class="optional">]</span><big>)</big><a class="headerlink" href="#urllib.URLopener.retrieve" title="Permalink to this definition">¶</a></dt>
<dd><p>Retrieves the contents of <em>url</em> and places it in <em>filename</em>.  The return value
is a tuple consisting of a local filename and either a
<a class="reference internal" href="mimetools.html#mimetools.Message" title="mimetools.Message"><tt class="xref py py-class docutils literal"><span class="pre">mimetools.Message</span></tt></a> object containing the response headers (for remote
URLs) or <tt class="xref docutils literal"><span class="pre">None</span></tt> (for local URLs).  The caller must then open and read the
contents of <em>filename</em>.  If <em>filename</em> is not given and the URL refers to a
local file, the input filename is returned.  If the URL is non-local and
<em>filename</em> is not given, the filename is the output of <a class="reference internal" href="tempfile.html#tempfile.mktemp" title="tempfile.mktemp"><tt class="xref py py-func docutils literal"><span class="pre">tempfile.mktemp()</span></tt></a>
with a suffix that matches the suffix of the last path component of the input
URL.  If <em>reporthook</em> is given, it must be a function accepting three numeric
parameters.  It will be called after each chunk of data is read from the
network.  <em>reporthook</em> is ignored for local URLs.</p>
<p>If the <em>url</em> uses the <tt class="file docutils literal"><span class="pre">http:</span></tt> scheme identifier, the optional <em>data</em>
argument may be given to specify a <tt class="docutils literal"><span class="pre">POST</span></tt> request (normally the request type
is <tt class="docutils literal"><span class="pre">GET</span></tt>).  The <em>data</em> argument must in standard
<em class="mimetype">application/x-www-form-urlencoded</em> format; see the <a class="reference internal" href="#urllib.urlencode" title="urllib.urlencode"><tt class="xref py py-func docutils literal"><span class="pre">urlencode()</span></tt></a>
function below.</p>
</dd></dl>

<dl class="attribute">
<dt id="urllib.URLopener.version">
<tt class="descname">version</tt><a class="headerlink" href="#urllib.URLopener.version" title="Permalink to this definition">¶</a></dt>
<dd><p>Variable that specifies the user agent of the opener object.  To get
<a class="reference internal" href="#module-urllib" title="urllib: Open an arbitrary network resource by URL (requires sockets)."><tt class="xref py py-mod docutils literal"><span class="pre">urllib</span></tt></a> to tell servers that it is a particular user agent, set this in a
subclass as a class variable or in the constructor before calling the base
constructor.</p>
</dd></dl>

</div></blockquote>
</dd></dl>

<dl class="class">
<dt id="urllib.FancyURLopener">
<em class="property">class </em><tt class="descclassname">urllib.</tt><tt class="descname">FancyURLopener</tt><big>(</big><em>...</em><big>)</big><a class="headerlink" href="#urllib.FancyURLopener" title="Permalink to this definition">¶</a></dt>
<dd><p><a class="reference internal" href="#urllib.FancyURLopener" title="urllib.FancyURLopener"><tt class="xref py py-class docutils literal"><span class="pre">FancyURLopener</span></tt></a> subclasses <a class="reference internal" href="#urllib.URLopener" title="urllib.URLopener"><tt class="xref py py-class docutils literal"><span class="pre">URLopener</span></tt></a> providing default handling
for the following HTTP response codes: 301, 302, 303, 307 and 401.  For the 30x
response codes listed above, the <em class="mailheader">Location</em> header is used to fetch
the actual URL.  For 401 response codes (authentication required), basic HTTP
authentication is performed.  For the 30x response codes, recursion is bounded
by the value of the <em>maxtries</em> attribute, which defaults to 10.</p>
<p>For all other response codes, the method <tt class="xref py py-meth docutils literal"><span class="pre">http_error_default()</span></tt> is called
which you can override in subclasses to handle the error appropriately.</p>
<div class="admonition note">
<p class="first admonition-title">Note</p>
<p class="last">According to the letter of <span class="target" id="index-7"></span><a class="rfc reference external" href="http://tools.ietf.org/html/rfc2616.html"><strong>RFC 2616</strong></a>, 301 and 302 responses to POST requests
must not be automatically redirected without confirmation by the user.  In
reality, browsers do allow automatic redirection of these responses, changing
the POST to a GET, and <a class="reference internal" href="#module-urllib" title="urllib: Open an arbitrary network resource by URL (requires sockets)."><tt class="xref py py-mod docutils literal"><span class="pre">urllib</span></tt></a> reproduces this behaviour.</p>
</div>
<p>The parameters to the constructor are the same as those for <a class="reference internal" href="#urllib.URLopener" title="urllib.URLopener"><tt class="xref py py-class docutils literal"><span class="pre">URLopener</span></tt></a>.</p>
<div class="admonition note">
<p class="first admonition-title">Note</p>
<blockquote>
<div>When performing basic authentication, a <a class="reference internal" href="#urllib.FancyURLopener" title="urllib.FancyURLopener"><tt class="xref py py-class docutils literal"><span class="pre">FancyURLopener</span></tt></a> instance calls
its <a class="reference internal" href="#urllib.FancyURLopener.prompt_user_passwd" title="urllib.FancyURLopener.prompt_user_passwd"><tt class="xref py py-meth docutils literal"><span class="pre">prompt_user_passwd()</span></tt></a> method.  The default implementation asks the
users for the required information on the controlling terminal.  A subclass may
override this method to support more appropriate behavior if needed.</div></blockquote>
<p>The <a class="reference internal" href="#urllib.FancyURLopener" title="urllib.FancyURLopener"><tt class="xref py py-class docutils literal"><span class="pre">FancyURLopener</span></tt></a> class offers one additional method that should be
overloaded to provide the appropriate behavior:</p>
<dl class="last method">
<dt id="urllib.FancyURLopener.prompt_user_passwd">
<tt class="descname">prompt_user_passwd</tt><big>(</big><em>host</em>, <em>realm</em><big>)</big><a class="headerlink" href="#urllib.FancyURLopener.prompt_user_passwd" title="Permalink to this definition">¶</a></dt>
<dd><p>Return information needed to authenticate the user at the given host in the
specified security realm.  The return value should be a tuple, <tt class="docutils literal"><span class="pre">(user,</span>
<span class="pre">password)</span></tt>, which can be used for basic authentication.</p>
<p>The implementation prompts for this information on the terminal; an application
should override this method to use an appropriate interaction model in the local
environment.</p>
</dd></dl>

</div>
</dd></dl>

<dl class="exception">
<dt id="urllib.ContentTooShortError">
<em class="property">exception </em><tt class="descclassname">urllib.</tt><tt class="descname">ContentTooShortError</tt><big>(</big><em>msg</em><span class="optional">[</span>, <em>content</em><span class="optional">]</span><big>)</big><a class="headerlink" href="#urllib.ContentTooShortError" title="Permalink to this definition">¶</a></dt>
<dd><p>This exception is raised when the <a class="reference internal" href="#urllib.urlretrieve" title="urllib.urlretrieve"><tt class="xref py py-func docutils literal"><span class="pre">urlretrieve()</span></tt></a> function detects that the
amount of the downloaded data is less than the  expected amount (given by the
<em>Content-Length</em> header). The <tt class="xref py py-attr docutils literal"><span class="pre">content</span></tt> attribute stores the downloaded
(and supposedly truncated) data.</p>
<p class="versionadded">
<span class="versionmodified">New in version 2.5.</span></p>
</dd></dl>

</div>
<div class="section" id="urllib-restrictions">
<h2>20.5.4. <a class="reference internal" href="#module-urllib" title="urllib: Open an arbitrary network resource by URL (requires sockets)."><tt class="xref py py-mod docutils literal"><span class="pre">urllib</span></tt></a> Restrictions<a class="headerlink" href="#urllib-restrictions" title="Permalink to this headline">¶</a></h2>
<blockquote>
<div></div></blockquote>
<ul id="index-8">
<li><p class="first">Currently, only the following protocols are supported: HTTP, (versions 0.9 and
1.0),  FTP, and local files.</p>
</li>
<li><p class="first">The caching feature of <a class="reference internal" href="#urllib.urlretrieve" title="urllib.urlretrieve"><tt class="xref py py-func docutils literal"><span class="pre">urlretrieve()</span></tt></a> has been disabled until I find the
time to hack proper processing of Expiration time headers.</p>
</li>
<li><p class="first">There should be a function to query whether a particular URL is in the cache.</p>
</li>
<li><p class="first">For backward compatibility, if a URL appears to point to a local file but the
file can&#8217;t be opened, the URL is re-interpreted using the FTP protocol.  This
can sometimes cause confusing error messages.</p>
</li>
<li><p class="first">The <a class="reference internal" href="#urllib.urlopen" title="urllib.urlopen"><tt class="xref py py-func docutils literal"><span class="pre">urlopen()</span></tt></a> and <a class="reference internal" href="#urllib.urlretrieve" title="urllib.urlretrieve"><tt class="xref py py-func docutils literal"><span class="pre">urlretrieve()</span></tt></a> functions can cause arbitrarily
long delays while waiting for a network connection to be set up.  This means
that it is difficult to build an interactive Web client using these functions
without using threads.</p>
</li>
<li id="index-9"><p class="first">The data returned by <a class="reference internal" href="#urllib.urlopen" title="urllib.urlopen"><tt class="xref py py-func docutils literal"><span class="pre">urlopen()</span></tt></a> or <a class="reference internal" href="#urllib.urlretrieve" title="urllib.urlretrieve"><tt class="xref py py-func docutils literal"><span class="pre">urlretrieve()</span></tt></a> is the raw data
returned by the server.  This may be binary data (such as an image), plain text
or (for example) HTML.  The HTTP protocol provides type information in the reply
header, which can be inspected by looking at the <em class="mailheader">Content-Type</em>
header.  If the returned data is HTML, you can use the module <a class="reference internal" href="htmllib.html#module-htmllib" title="htmllib: A parser for HTML documents. (deprecated)"><tt class="xref py py-mod docutils literal"><span class="pre">htmllib</span></tt></a> to
parse it.</p>
</li>
<li id="index-10"><p class="first">The code handling the FTP protocol cannot differentiate between a file and a
directory.  This can lead to unexpected behavior when attempting to read a URL
that points to a file that is not accessible.  If the URL ends in a <tt class="docutils literal"><span class="pre">/</span></tt>, it is
assumed to refer to a directory and will be handled accordingly.  But if an
attempt to read a file leads to a 550 error (meaning the URL cannot be found or
is not accessible, often for permission reasons), then the path is treated as a
directory in order to handle the case when a directory is specified by a URL but
the trailing <tt class="docutils literal"><span class="pre">/</span></tt> has been left off.  This can cause misleading results when
you try to fetch a file whose read permissions make it inaccessible; the FTP
code will try to read it, fail with a 550 error, and then perform a directory
listing for the unreadable file. If fine-grained control is needed, consider
using the <a class="reference internal" href="ftplib.html#module-ftplib" title="ftplib: FTP protocol client (requires sockets)."><tt class="xref py py-mod docutils literal"><span class="pre">ftplib</span></tt></a> module, subclassing <a class="reference internal" href="#urllib.FancyURLopener" title="urllib.FancyURLopener"><tt class="xref py py-class docutils literal"><span class="pre">FancyURLopener</span></tt></a>, or changing
<em>_urlopener</em> to meet your needs.</p>
</li>
<li><p class="first">This module does not support the use of proxies which require authentication.
This may be implemented in the future.</p>
</li>
<li id="index-11"><p class="first">Although the <a class="reference internal" href="#module-urllib" title="urllib: Open an arbitrary network resource by URL (requires sockets)."><tt class="xref py py-mod docutils literal"><span class="pre">urllib</span></tt></a> module contains (undocumented) routines to parse
and unparse URL strings, the recommended interface for URL manipulation is in
module <a class="reference internal" href="urlparse.html#module-urlparse" title="urlparse: Parse URLs into or assemble them from components."><tt class="xref py py-mod docutils literal"><span class="pre">urlparse</span></tt></a>.</p>
</li>
</ul>
</div>
<div class="section" id="examples">
<span id="urllib-examples"></span><h2>20.5.5. Examples<a class="headerlink" href="#examples" title="Permalink to this headline">¶</a></h2>
<p>Here is an example session that uses the <tt class="docutils literal"><span class="pre">GET</span></tt> method to retrieve a URL
containing parameters:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="gp">&gt;&gt;&gt; </span><span class="kn">import</span> <span class="nn">urllib</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">params</span> <span class="o">=</span> <span class="n">urllib</span><span class="o">.</span><span class="n">urlencode</span><span class="p">({</span><span class="s">&#39;spam&#39;</span><span class="p">:</span> <span class="mi">1</span><span class="p">,</span> <span class="s">&#39;eggs&#39;</span><span class="p">:</span> <span class="mi">2</span><span class="p">,</span> <span class="s">&#39;bacon&#39;</span><span class="p">:</span> <span class="mi">0</span><span class="p">})</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">f</span> <span class="o">=</span> <span class="n">urllib</span><span class="o">.</span><span class="n">urlopen</span><span class="p">(</span><span class="s">&quot;http://www.musi-cal.com/cgi-bin/query?</span><span class="si">%s</span><span class="s">&quot;</span> <span class="o">%</span> <span class="n">params</span><span class="p">)</span>
<span class="gp">&gt;&gt;&gt; </span><span class="k">print</span> <span class="n">f</span><span class="o">.</span><span class="n">read</span><span class="p">()</span>
</pre></div>
</div>
<p>The following example uses the <tt class="docutils literal"><span class="pre">POST</span></tt> method instead:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="gp">&gt;&gt;&gt; </span><span class="kn">import</span> <span class="nn">urllib</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">params</span> <span class="o">=</span> <span class="n">urllib</span><span class="o">.</span><span class="n">urlencode</span><span class="p">({</span><span class="s">&#39;spam&#39;</span><span class="p">:</span> <span class="mi">1</span><span class="p">,</span> <span class="s">&#39;eggs&#39;</span><span class="p">:</span> <span class="mi">2</span><span class="p">,</span> <span class="s">&#39;bacon&#39;</span><span class="p">:</span> <span class="mi">0</span><span class="p">})</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">f</span> <span class="o">=</span> <span class="n">urllib</span><span class="o">.</span><span class="n">urlopen</span><span class="p">(</span><span class="s">&quot;http://www.musi-cal.com/cgi-bin/query&quot;</span><span class="p">,</span> <span class="n">params</span><span class="p">)</span>
<span class="gp">&gt;&gt;&gt; </span><span class="k">print</span> <span class="n">f</span><span class="o">.</span><span class="n">read</span><span class="p">()</span>
</pre></div>
</div>
<p>The following example uses an explicitly specified HTTP proxy, overriding
environment settings:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="gp">&gt;&gt;&gt; </span><span class="kn">import</span> <span class="nn">urllib</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">proxies</span> <span class="o">=</span> <span class="p">{</span><span class="s">&#39;http&#39;</span><span class="p">:</span> <span class="s">&#39;http://proxy.example.com:8080/&#39;</span><span class="p">}</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">opener</span> <span class="o">=</span> <span class="n">urllib</span><span class="o">.</span><span class="n">FancyURLopener</span><span class="p">(</span><span class="n">proxies</span><span class="p">)</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">f</span> <span class="o">=</span> <span class="n">opener</span><span class="o">.</span><span class="n">open</span><span class="p">(</span><span class="s">&quot;http://www.python.org&quot;</span><span class="p">)</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">f</span><span class="o">.</span><span class="n">read</span><span class="p">()</span>
</pre></div>
</div>
<p>The following example uses no proxies at all, overriding environment settings:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="gp">&gt;&gt;&gt; </span><span class="kn">import</span> <span class="nn">urllib</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">opener</span> <span class="o">=</span> <span class="n">urllib</span><span class="o">.</span><span class="n">FancyURLopener</span><span class="p">({})</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">f</span> <span class="o">=</span> <span class="n">opener</span><span class="o">.</span><span class="n">open</span><span class="p">(</span><span class="s">&quot;http://www.python.org/&quot;</span><span class="p">)</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">f</span><span class="o">.</span><span class="n">read</span><span class="p">()</span>
</pre></div>
</div>
</div>
</div>


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<li><a class="reference internal" href="#">20.5. <tt class="docutils literal"><span class="pre">urllib</span></tt> &#8212; Open arbitrary resources by URL</a><ul>
<li><a class="reference internal" href="#high-level-interface">20.5.1. High-level interface</a></li>
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